Well...I can confirm what Autodesk said and it also affects Resolve 9 and 10
I do not have smooth playback in 4 projects I just checked after installing Mavericks on our beefy company machine running 3 GTX 680s
Blackmagic Speedtest reports 700 mb/s read and write but playback in Resolve is hitting only 22 fps on a SD PAL uncompressed project with 5 nodes.